A slider for a slide fastener includes an upper blade, an a lower blade, a guide post for connecting one end portions of the upper blade and the lower blade to each other with a passage gap for elements between the upper blade and the lower blade, a pull tab attachment rod erected from an upper surface of one end of the upper blade, which is located toward the guide post, and extending toward the other end portion, and a pull tab attached to the pull tab attachment rod. The pull tab is attached to the pull tab attachment rod by inserting an attachment shaft portion of the pull tab into a pull tab receiving space between the pull tab attachment rod and the upper surface of the upper blade. In general sliders, after the attachment shaft portion of the pull tab is set in the pull tab receiving space between the pull tab attachment rod and the upper surface of the upper blade, both ends of the pull tab attachment rod are immovably fixed at predetermined positions on the upper surface of the upper blade of the slider body. Accordingly, in such sliders, various pull tabs different in color, pattern, shape or the like cannot be freely attached to the slider body depending on needs or preferences of customers and thus the pull tab cannot be arbitrarily substituted once the pull tab is attached to the slider body.
Instead of such conventional general sliders, many sliders in which a pull tab is attached afterward to a slider body have been also proposed. The typical proposals are disclosed, for example, in WO2010/058465A1 (Patent Document 1), WO2011/086703A1 (Patent Document 2) and the like. According to Patent Documents 1 and 2, a pull tab holding body (pull tab attachment rod) is fixedly installed in cantilever fashion on an upper surface of an upper blade of a slider body in such a manner that one end of the pull tab holding body (pull tab attachment rod) is fixed on a guide post-side end portion, which is a front end portion of the upper surface of the upper blade of the body, and the other end becomes a free end. In this case, the slider disclosed in Patent Document 1, the pull tab holding body and the slider body are separately manufactured and thus upon mounting of the slider, the pull tab holding body is mounted and fixed on the slider body. Meanwhile, in the slider disclosed in Patent Document 2, one end of the pull tab attachment rod is integrally molded in cantilever fashion on one end of the slider body. In either slider, an insertion gap through which an attachment shaft portion of the pull tab can be inserted is formed between the free end of the pull tab attachment rod and the upper blade and is closed by a closure body or a blocking member which is separately prepared after the attachment shaft portion of the pull tab is inserted through the gap.
In the post-attaching type slider disclosed in Patent Document 1, the closure body is slidingly guided in a forward and rearward direction along a sliding path provided on the upper surface of the upper blade for regulating movement in a right and left slider width direction and in an upward and downward direction perpendicular to the upper blade, from the insertion gap at a rear mouth side of the upper blade, which is opposite to the guide post side thereof, to the middle of the pull tab receiving space at the guide post side thereof. The sliding path in Patent Document 1 is a dovetail groove formed so that opening edges formed along right and left end portions of the upper blades are opposed to each other. Meanwhile, on right and left rear end portions of the pull tab holding body, also, a sliding groove having U-shaped cross section is formed so that opening edges thereof are opposed to each other. A guide piece formed along a lower end edge of the closure body and guide pieces formed in a flange shape along right and left upper end edge portions of the closure body are respectively inserted into the dovetail groove and the sliding groove, so that the insertion gap between the pull tab holding body and the upper blade is closed by the closure body, and at the same time the closure body is fixedly held on the pull tab holding body and the upper blade in the upward and downward direction and the right and left direction. As used herein, as to the slider, the upper side means a side of the upper blade, on which the pull tab is attached. On a rear end-side half of the upper surface of the upper blade, a rear recessed portion is formed.
In such configurations, the closure body is set on the rear end portion of the upper surface of the upper blade, and then short protrusion pieces erected on right and left rear end portions of the upper blade of the slider body are previously bent to be generally parallel to the upper surface of the upper blade by crimping. In this case, in order to attach the pull tab to the slider body, a front end portion of the pull tab holding body is fitted and fixed to a front end portion of the upper blade, and at the same time an upper guide piece of the closure body is fitted into the sliding groove arranged in a rear end portion of the pull tab holding body. At this time, a coil spring is previously arranged in the rear recessed portion formed in the upper surface of the upper blade and then the closure body is moved forward at a predetermined position against an elastic force of the coil spring. Then, the attachment shaft portion of the pull tab is inserted through the pull tab insertion gap between the free end of the pull tab holding body and the upper blade, and the pull tab is set at a predetermined position after being received in a part of the pull tab receiving space between the upper blade and the pull tab holding body formed in front of the closure body. When setting is ended, the closure body is moved to an inlet of the insertion gap along the rear recessed portion by an elastic force of the coil spring exerted rearward from the front side thereof. At this time, rear end surfaces of the guide pieces protruding outward along the right and left lower end edges of the closure body comes in contact with front end surfaces of the right and left short protrusion pieces, which are located on the guide post side and the short protrusion pieces serve as a stopper, so that the closure body cannot be retracted further.
In the slider having the pull tab attached to in this way, the pull tab can be detached from the slider body. In order to separate the pull tab, the closure body is first advanced to a position, at which a space through which the pull tab can pass is formed between an upper surface of the closure body and an inner surface of the pull tab holding surface, against an elastic force of the coil spring. In this case, the closure body is remained at that position in a stopped state and then the attachment shaft portion of the pull tab is separated from the part of the pull tab receiving space between the pull tab holding body and the upper blade, thereby detaching the pull tab from the slider body. Subsequently, when restriction of the closure body remained in the middle of the pull tab receiving space is released, the closure body can be easily returned to a position, at which the closure body comes in contact with the short protrusion pieces, by the elastic force of the coil spring and the pull tab is continuously pulled out to be drawn out from the insertion gap. Thus, in the slider proposed in Patent Document 1, the pull tab can be substituted in situ depending on preferences of customers because the pull tab can be freely attached and detached afterward.
Meanwhile, according to the post-attaching slider proposed in Patent Document 2, the slider body and the pull tab attachment rod are initially integrally formed with each other. In the slider described in Patent Document 2, like Patent Document 1, the pull tab attachment rod is integrated in cantilever fashion in such a manner that one end thereof is fixedly installed on the guide post-side end portion of the upper blade of the slider body and the other end becomes a free end portion, and thus an insertion gap through which the attachment shaft portion of the pull tab can be inserted is formed between the free end portion and the upper blade. In a rear end-side half portion of the middle portion, in a width direction, of the upper surface of the upper blade, a rectangular recessed groove is formed to extend to the rear end thereof and a blocking member for closing the inserting gap is fitted in the recessed groove. Also, a leading end of the free end portion of the pull tab attachment rod is of a hook shape curved downward, and a locking step portion adapted to be locked with the blocking member is formed on a lower surface of the hook-shaped leading end portion.
In a first example of typical blocking members disclosed in Patent Document 1, right and left arm portions are provided to horizontally extend rearward in parallel from right and left shoulder portions of a body thereof in a width direction, and also elastic piece portion are likewise provided between the right and left shoulder portions to extend in the same direction as that of the right and left arm portions. The right and left shoulder bodies and the right and left arm portions are formed of a rigid body, and the elastic piece portions have a lodged L-shaped longitudinal section and are elastically deformed at leading ends thereof about bent base end portions in an upward and downward direction. The front end surfaces of the elastic piece portions including the right and left shoulder portions are formed by inclined surfaces inclined downward toward the front thereof, which is the guide post side thereof, and a locking/separating step portions adapted to be locked on and separated from the leading locking step portions of the pull tab attachment piece are provided on the middles of the upper surfaces of the elastic piece portions. A dimension between outer side surfaces of the right and left arm portions including the right and left shoulder portions is equal to a dimension between right and left inner wall surfaces of the rectangular recessed groove, and a dimension between front end surfaces of the shoulder portions and rear end surfaces of the right and left arm portions is equal to a dimension between a front end and a rear end of the recessed groove. A height of the elastic piece portions in the upward and downward direction is equal to a dimension between a bottom surface of the recessed groove of the upper blade and an upper surface of the locking/separating step portions of the pull tab attachment rod. The inclined surfaces is configured to define a large pull tab attachment space between the pull tab attachment rod and the upper blade and to serve as an guide surface for guiding the pull tab so that when the pull tab is pulled rearward to close the slide fastener, a stopped position of the pull tab enters the leading hook-shaped curved portions of the pull tab attachment rod.
In the slider having such configurations, in order to attach the pull tab to the slider body, the attachment shaft portion of the pull tab is inserted through the insertion gap between the free end portion of the pull tab attachment rod and the upper blade, and subsequently, the blocking member is inserted, at the shoulder portions thereof, into an inlet of the recessed groove formed in the upper surface of the upper blade and then is further pushed inward. Upon pushing, the leading end of the pull tab attachment rod pushes the upper surfaces of the elastic piece portions downward from above so that the elastic piece portions are elastically deformed downward. When the locking/separating step portions of the elastic piece portions reach a locking position, at which the locking step portion of the pull tab attachment rod is to be locked therewith, while keeping the elastically deformed state, the elastic piece portions are released from pushing by the leading end surface of the pull tab attachment rod from above and thus elastically returned to an original state. Thus, the locking/separating step portions of the elastic pieces portions are locked on the locking step portion of the pull tab attachment rod, and as a result attaching of the pull tab is completed. In order to detach the pull tab from the slider to which the pull tab is attached, the upper surfaces of the rear ends of the elastic piece portions are pushed to be elastically deformed, so that locking between the locking/separating step portions and the locking step portion is released. Then, the blocking member is moved forward along the recessed groove formed in the upper surface of the upper blade and the attachment shaft portion of the pull tab is drawn out from the insertion gap between the free end of the pull tab attachment rod and the upper blade.
Also, according to a second example of blocking members disclosed in Patent Document 2, the pull tab attachment rod is fixedly installed in cantilever fashion on the upper surface of the shoulder mouths-side end portion (front end portion) of the upper blade of the slider body, and an insertion gap through and from which the attachment shaft portion of the pull tab can be inserted and separated is formed between a rear end thereof and the upper blade. Also, on a leading end of the pull tab attachment rod, one headed pin portion is provided to horizontally protrude rearward. An omission portion is formed by removing a rear end surface of the upper blade by a required height, and on the middle of the remained portion in the width direction, a body insertion space, which is opened upward and has dovetail groove on right and left sides thereof, is formed to allow a main body portion, as described below, of the blocking member to be inserted therein. A bottom surface of the body insertion space is arranged to be flushed with a bottom surface of the omission portion. A guide groove for fitting and guiding a part of the main body portion of the blocking member in a forward and rearward direction is formed on the bottom surface of the body insertion space and the middle, in the width direction, of the surface of the omission portion. In addition, on the bottom surface of the omission portion, right and left protrusion portions are arranged to face the rear end surfaces of the right and left dovetail grooves.
Meanwhile, the blocking member according to the second example described in Patent Document 2, includes a rectangular flat plat-shaped main body portion fitted into the right and left dovetail grooves of the upper blade to be horizontally mounted thereon, an elastic piece portion erected upward from the front end of the main body portion to be curved in a S-shape as viewed from the side thereof and adapted to be elastically deformable in the upward and downward direction, a hole portion formed to extend through the middle of a free end of the elastic piece portion in the forward and rearward direction, a pair of right and left leg portions horizontally extending rearward from the main body portion to be bifurcated and gradually expanded, locking protrusion pieces provided respectively on leading ends of the leg portions to protrude in right and left directions away from each other, and a ridge portion extending to linearly protrude from the middle, in the width direction, of a lower surface of the main body portion. The ridge portion is fitted into the guide groove formed in the middle, in the width direction, of the bottom surface of the upper blade to be slidingly guided in the forward and rearward direction. The hole portion is detachably locked on a head of the headed pin portion formed on the leading end of the pull tab attachment rod. The pair of right and left leg portions can be elastically deformed in the right and left direction (slider width direction).
In such configurations, in order to attach the pull tab to the slider body, the attachment shaft portion of the pull tab is inserted in the pull tab receiving space through the insertion gap between the free end of the pull tab attachment rod and the upper blade, and the main body portion and the right and left leg portions of the blocking member are fitted into the dovetail groove in the upper surface of the upper blade and then are moved forward. During moving, the headed pin portion protruding from the leading end of the free end portion of the pull tab attachment rod is inserted and locked in the hole portion of the upper end of the elastic piece portion of the blocking member. The pair of right and left leg portions, which are being guided along the dovetail groove and moved forward, are elastically deformed as they are advanced so that a distance therebetween in the right and left direction is narrowed. Thus, until a forward curved surface of the S-shaped elastic pieces comes in contact with an inner wall surface of the body insertion space of the upper blade, the right and left leg portions are forcibly elastically deformed so that a distance between leading ends of the locking protrusion pieces provided on the leading ends of the right and left leg portions becomes narrower than an opposing distance between the right and left protrusions erected from the upper surface of the omission portion of the upper blade. When the blocking member is continuously moved in such an elastically deformed state and thus the right and left locking protrusion pieces reach a position of a gap between the vicinity of the rear end surfaces of the right and left dovetail grooves of the upper blade and the right and left protrusions, the elastic deformation force is released so that the locking protrusion pieces are automatically invaded and thus the blocking member is prevented from being further advanced or retracted. Meanwhile, in order to detach the pull tab from the slider body, complex reverse operations have to be performed. Thus, as compared to the first example as described above, the pull tab can be detached, but not easy.
Meanwhile, as sliders having a special structure used for a specified application, a locking slider disclosed in Japanese Utility Model Application Publication S53-36903 (Patent Document 3) is known. The slider is widely used for example in bags, in which a strong force is likely to be exerted on a pull tab, and is used in such a manner that a pair of locking sliders are mounted on a slide fastener chain so that shoulder mouths thereof face each other. On a shoulder mouths-side middle end portion of an upper blade of each of the pair of locking sliders, a locking metal fitting formed by a half-circular metal ring, which is provided with a lock insertion hole, is integrally attached to the upper blade to protrude outward from the upper blade. When locking is needed, the lock insertion holes of the pair of locking metal fittings are overlapped with each other and then a lock rod is inserted through each lock insertion hole, thereby providing locking.
Like Patent Documents 1 and 2, the slider described in Patent Document 3 is entirely also composed of aluminum alloy, copper alloy, zinc alloy or the like. The reason is that metals have a good wear resistance as well as rigidity and strength higher than other materials and also is plastically deformable so that desired products can be obtained by performing in combination or solely machinings, such as die-casting, pressing, crimping or cutting. For example, in Patent Document 1, also, the slider body is molded by die-casting and then when the pull tab is attached thereto, so-called crimping is performed in which a pair of short pieces erected from right and left corners on the shoulder mouths side of the upper surface of the upper blade are pushed and bent at leading ends thereof in direction approaching to each other.